
I have a condensing combi boiler. I keep mine on the all day setting but thermostat in hall only at 15'C so ti doesn't come on that much.
Then if anyone feels chilly at any time we just push the thermo up to about 17, and ti warms up a bit.
I had been told it is better/cheaper to have the CH on most of the day at low levels than it having to warm the house from scratch.
If we go away for a few days then it is left on at 10'C, so only coming on at all if it is freezing outdoors.
My Bristol brick built 1930's ex LA 3 bed end of terrace costs me £26 a month on this regime to heat (British Gas). On the other hand I can barely get my Electricity to stay at £50 a month.
Just got my bills and I am £50+ in debit on Electricity and £20+ in credit on Gas, as of course this was the hungriest heating quarter.